Molecular computation and circuits engineering (1-27) using a “silicomimetic” approach is currently focused on building molecular networks analogous to electrical engineering designs. These networks consist of logic gates, which perform Boolean logical operations such as AND, NOT, and OR on one or more inputs to produce an output. While individual molecular gates and small networks have previously been constructed, these gates are yet to be integrated at higher levels of complexity. Such integration in electrical engineering arises from massive parallelism and interconnections, rather than fundamental component complexity. The ability to truly integrate molecular components remains crucial for the construction of next-generation molecular devices (11, 14).
The largest solution-phase molecular circuits previously considered include networks combining up to 20 logic modules (11-20). On a similar scale, utilizing a full set of deoxyribozyme-based logic gates (6, 19, 24), solution-phase computing circuits have been constructed such as a half-adder (7), ligase-phosphodiesterase cascades (19), and most recently a full-adder that comprises 7 logic gates in a single tube (24).